Racing over three legs, each 3km, Nicole Taylor, Lucy Reid and Ashley Gibson pulled away from Aldershot in the second half of the race to win by 34 seconds.
Conditions were unseasonably dry, which helped produce fast times. Taylor came home in second place out of 139 starting teams, with a 9min 34sec split, on the slightly shorter first leg.
She trailed Team GB international Emily Hosker-Thornhill of Aldershot but had managed to set Tonbridge up to make a real impact.
Reid took off on the second leg and made immediate inroads into Aldershot’s lead, going on to put Tonbridge more than 20 seconds ahead.
It was down to Gibson to keep her composure and bring the team home. She did this in fine style, clocking 10.01 to take the win ahead of Aldershot, with Rotherham in third place.
The Under-13 girls’ team snatched victory at the very end of their race, over three legs of 2km. Lily Slack ran 7.14 on the opening leg, which put the team eight seconds behind the leaders St Albans.
Sophie Slack (7.39) kept the team in second place but dropped a further ten seconds behind.
Olivia Breed clawed her way back towards the leader on the last leg, however, finally catching her up the final hill with 200 metres to go.
Breed ran her leg in 7.17, the fastest time of the longer second and third lap runners, to win by just one second in 22.11.
The Under-20 men came close to victory, too, after they took the lead on the final leg of three in their race but lost out to Morpeth by ten seconds.
Jamie Goodge ran 8.57 on the opening leg, and in-form Alasdair Kinloch then set about making gains, his 8.48 putting the team in fifth place.
A few seconds separated several teams and James Puxty chasied hard, eventually taking the lead at around halfway.
However, Morpeth’s Rory Leonard eventually took Puxty with about a kilometre to go. Puxty ran 8.55 to win the silver medal for Tonbridge.
The men’s team event was run over four legs of 5km and Tonbridge put up a respectable display in trying to defend the title they won last year.
This time they just missed out on the medals and finished fourth behind Leeds, Aldershot and Birchfield in a field of almost 200 teams; Dom Brown ran 15.14, Corey De’Ath 15.19, George Duggan 15.30 and Ryan Driscoll 15.32.
The Under-13 boys’ team of Albert Kreuzberg (6.47), Tim McLain (7.26) and George Hopkins (7.02) finished fourth, 12 seconds away from the bronze medal time.
The Under-17 men finished an excellent fifth from 96 teams over three laps of 3km, thanks to James Kingston (8.59), Toby Emm (9.30) and Fraser Gordon (9.17).
The Under-15 boys Matthew Dubery (6.47), Matthew Taylor (6.25) and Henry Taylor (6.47) came eighth over 2km, the Under-17 women finished 32nd and the Under-20 women 21st.